Just an update, left the Champions in since removing the NGK`s that were missing so badly.With the Champions in the missing was down to 5% of what it was, and did not seem to deteriorate from there.
Due to the collective wisdom of members on this forum, I was now suspecting overfueling sooting up the plugs was the real culprit, so I looked over the carbs. The plug chops were showing pretty black, rear carb more so than the front even though settings identical,so i swapped out the rear float needle for a NOS one i had. I had originally re-assembled the carbs that were with the bike with all their original components, as they looked OK, so i thought "try `em out and see" but the rear carb was always close to "drippy" at best.Truth is, rear needle did look a bit ridged up close when i really looked.
With the new float needle in, there has been immediate further improvement, i.e. a step down in misfiring from 5% to just a slight ,occasional hiccup, the bike now runs pretty cleanly,and pulls surprisingly well, its almost spot on. I feel (hope) a further tweak of the slides may clear up the remaining richness and clear the misfire completely, we shall see. The interesting point here,is that after suspecting interference from the plug leads scrambling the mag and causing the misfire, i shifted the coils to a remote spot and got no result- in fact worse, as when I did that, I was running the then new NGK`s that went down in just a few miles. On swapping back to the used Champions, and immediately getting such a dramatic improvement, I decided to return the coils back to their place under the mag cowl, all crammed in, and doing so did not worsen the situation at all, (bearing in mind that I have always run the kill wire round the timing side of the front pot to keep it away from the coils/leads.) Thus it seems that the mag is, and always has been fine, although i have not completely cleared the misfire yet so cannot exonerate it absolutely,but my further attention will be on fuelling refinement, not the mag. I`ll keep you posted, Bob.
